There are no answers, just theories, so far Algae, bacteria, and coronavirus lockdown have been cited as possible reasons why the Lonar Crater Lake turned pink.
Experts noted that Lonar Lake’s water had changed color before but never in such a drastic manner. It is a topic of discussion among scientists, forest department, and nature lovers as a 56,000-year-old lake in Maharashtra, India has turned pink.
Lonar Crater Lake is also called “Soda Lake” due to its unusual geochemistry which enables the growth of specific types of microorganisms, some of which are not found anywhere else in the world.
The deputy conservator of the Maharashtra of the Forest Department, MN Khairnar said that: “We are observing the phenomenon to such an extent for the first time, e ill collect samples of the lake water for testing to find the reason behind the occurrence. These samples will be sent to Neeri, Nagar, and Agarkar Research Institute Pune.”
Located inside the Deccan Plateau, part of the Lonar sanctuary stretching over 1.8 kilometers of protected land in Maharashtra, The Lonar Crater Lake was created due to a meteorite impact and the craters that formed are among the most interesting geological structures on the planet. A crater is a bowl-shaped depression or hollowed-out area, produced by the impact of a meteorite, volcanic activity, or an explosion.
The Lake is located in the world’s only high velocity, impact crater in basaltic rock. Scientists claim that the crater was formed when a meteorite or asteroid hit the area at a speed of 90,000 kmph.
The abrupt color change occurred overnight in mid-June 2020, the issue has been theorized by many. The first theory is that the dry season could be affecting the lake’s water level increasing the salinity as water level shrinks and therefore triggering a bloom of red algae.
MS Reddy, the Principal Chief conservator of forests explained that high salinity in bodies of water can also encourage the growth of Dunliella algae which is typically green.
The levels of salinity combined with warming temperatures could trigger the production of protective carotenoids which are responsible for pigmentation in bright-colored vegetables like carrots.
Another theory which seems to depict the reason behind the pink water is – high alkaline – due to lake’s high concentration of carbonate salt – inside the lake is typically related to the growth of bacteria called Halobacteriaceae.
Reddy said, “The halobacteria also uses a red pigment to absorb the sunlight and convert it into energy. This also turns the water red.”
Another theory that has been propped up by experts is — human inactivity.
Air and water quality has improved a lot due to the global lockdown during the COVID-19 pandemic. Madan Suryavashi, head of the geography department at Maharashtra’s Babasaheb Ambedkar University said that the loss of human activity in a country with 1.3 billion population could have an influence on the lake’s ecosystem.
“This [Dunaliella] algae, under such circumstance, turns red in color,” he said. Reddy likened the phenomenon at Lonar Crater Lake, which has a pH of 10.5, to the appearance of pink water documented at Iran’s Umria lake. He further added, ” We will only know the exact causes once our scientific analysis is complete in a few days”. Experts wait for the results of the investigation before they can draw any definitive conclusions.